Multiunit electric terminal and indicator panel assembly and components



Aug- 7, 1965 .1. H. ANDERSEN ETAL 3,201,786

MULTIUNIT ELECTRIC TERMINAL AND INDICATOR PANEL ASSEMBLY AND COMPONENTSFiled June 12, 1961 2 Sheets-Sheet l INVENTOR. JAMES H. ANDEKSEN BYMAUR/(E UFULLEI? ATTORIYEXS Aug. 17, 1965 J. H. ANDERSEN ETAL 3,201,786

MULTIUNIT ELECTRIC TERMINAL AND INDICATOR PANEL ASSEMBLY AND COMPONENTSFiled June 12, 1961 2 Sheets-Sheet 2 IN VEN TOR.

. 2% JAMESHANDEESEN BY MA UE/(E D. FULL E 2 3870x651! {Z61 United StatesPatent 0 3.201 786 MULTIUNIT ELECTRIC iERMINAL AND INDI- CATUR PANELASSEMBLY AND COMPGNENTS James H. Andersen, Mountlake Terrace, andMaurice D.

Fuller, Seattle, Wash, assignors to Kerry Manufacturing -Co., Seattle,Wash, a corporation of Washington Filed June 12, 1961, Ser. No. 116,52823 Claims. (Cl. 340381) This invention relates to improvements in theconstruction of indicator and electric terminal assemblies andcomponents thereof, and more particularly concerns panel assemblieswherein one or more individual indicator or electric terminal units aremounted in an opening in a supporting panel. One application of theinvention, for example, relates to airplane indicator panels in which anumber of lamp-illuminated indicator uni-ts are grouped in selectedarrangements. The invention is herein illustrati-vely described byreference to the presently preferred embodiment thereof; however, itwill be recognized that certain modifications and changes therein withrespect to details may be made without departing from the underlyingessentials involved.

An important object of the invention is to provide improved mounting andsupporting structures and components for multiunit terminal panelassemblies and the like, which are of practicable, economical form,adapted for use in a wide variety of applications, compact, and quicklyand easily assembled and disassembled without specialized toolingrequirements.

A related object is to provide improved indicator structures of thedescribed type which are highly compact, adapted for modulardimensioning, and versatile in terms of the wide varietyof arrangementsof units within a panel opening which may be achieved in order tosatisfy different design requirements (i.e., by arranging the units inrows and columns, staggered wit-h different orientations of the broadand narrow width dimensions, etc).

A further object is to provide improved apparatus of the type describedwherein the parts are of simple, rugged construction and suited for longand trouble free operation.

Still another object is to provide improved indicator unit structures inwhich individual units, or merely the lamp devices within those units,are readily removed and replaced without disturbing the adjacent unitsor, in the case of lamp device removal only, the associated housing,thereby greatly expediting .and facilitating checking and repairing ofcircuits, replacement of defective lamps, etc.

Still another object is an improved indicator panel assembly in whichany or all of the individual units are conveniently mountable andremovable by use of a single tool, preferably .an ordinary screwdriver,and wherein the securing elements are readily and directly accessiblefor this. purpose from space directly behind the panel Without necessityfor awkward maneuvering and manipulations of the tool.

Yet another object is an improved securing system and means by whichindividual indicator units are secured together and by which theperipherally located units within a group of such units mounted in anindicator panel opening are secured to the edges of the panel at theopening. The novel multipurpose securing means employed herein hasgeneral application to the securing together of any of differentmutually superposed elements, and is not necessarily restricted inapplication to lamp device housings as herein disclosed.

A related object of the invention is to provide a novel securing meansby which two mutually superposed elements may be fastened together,especimly plate-like elements, by use of a single securing screwaccessible at and operated from one end of the elements.

It is a specific object to provide a novel means for securing anindicator unit to the edge of a panel by operation of a clamp screwaccessible from the rear of the panel, and a cooperable front edgingstrip which closes oil and improves the appearance of the front of thepanel by covering the interface and edges of the panel opening andadjacent .indicator unit sides. This edging strip, preferably of aplastic material, such as nylon, also serves as a gasket which isslightly compressed as the securing clamp elements are tightened andthereby assures a uniformly tight and vibration-resistant connection ofthe units to the panel.

A further object is an improved latching means operable to hold anindicator lamp device or the like releasably to and within a lamp devicehousing. The improved latching means comprises inconspicuous, protected,yet conveniently accessible operating elements which are so formed as tooccupy negligible space within a compact lamp unit housing and so as topermit direct actuation thereof conveniently from the front of thepanel. These latching elements in conjunction with the manner in whichthe lamp devices are mounted in their housings permit easy removal ofindividual lamp devices without disturbing adjacent units or thehousings themselves.

Still another object is to provide an improved lamp typeindicat-or unitor other piug-and-socket electric terminal assembly having a novel meansboth for sealing around the terminal contact elements and for initiallyso ejectin the lamp device partially from its seated position when itslatching means are released as to permit easily grasping the lamp devicefor complete removal.

While the invention is herein illustratively described in the form of amultiunit electric lamp-type indicator panel assembly and componentsthereof, it will be appre ciated that certain features have applicationin other devices as well.

In accordance with the invention in one aspect an openend housingreceives a c-omplementally formed lamp device normally latched in seatedposition in the housing by novel latch means comprisin elongated,resilient, edgewisea-actuatable latch arms which project forwardlythrough narrow spaces formed between housing and lamp device to thefront end of the housing for manual operating accessibility. A relatedfeature resides in the interpositioning of an apertured elastomericmaterial pad be tween the interior end wall of the housing and the baseWall of the indicator lamp device, such pad being aperture'd to passelectrical contact elements. This resilient pad is compressed in theseated position of the indicator unit in the housing, and thereby formsa moisture seal surrounding the electric terminal contacts, as well asserving as a means to partially eject the indicator unit, enabling it tobe grasped conveniently upon release of the latch means.

Other features reside in the novel means for securing together aplurality of superposed elements, such as the adjacent sides ofindicator unit housings, or one such side and a cooperating indicatorunit mounting bracket, such means featuring coincident slots formed insaid elements, each having a relatively narrow entrance portion and arelatively wide base portion connected thereto through a transitionalportion, with a first fastener element preferably in the form of agrooved nut lodged in the base portion and drawn over the adjacenttransitional portions of the elements preferably by means of a screwengaging the nut and reacting against the end edges of the superposedelements. By such a means mutually adjacent indicator units are securedtogether in the novel indicator panel assemblies. Furthermore, by such ameans a novel panel-engaging mounting means, incorporating still otherfeatures of the invention, is secured to the peripherally exposed sideof each peripherally located indicator unit of a group of such unitsmounted within a panel opening. The novel mounting bracket extendsthrough a gap between the edge of the panel opening and the adjacentside of the indicator unit and carries an outwardly directed flangebetween which and a clamp screw carried by the mounting bracket theindicator panel is clamped in order to hold the units in positiontherein.

These and other features, objects and advantages of the invention willbecome more fully evident from the following description thereof byreference to the accompanying drawings.

FIGURE 1 is a perspective view of a single indicator unit mounted in apanel, portions of which are broken away to illustrate certain featuresof the invention.

FIGURE 2 is an exploded isometric view showing certain of the componentsemployed in the installation of FIGURE 1.

FIGURE 3 is a rear end view of the indicator unit shown in FIGURE 1.

FIGURE 4 is a transverse sectional view taken through a verticallongitudinal'midplane in FIGURE 1.

FIGURE 5 is an enlarged detail illustrating the novel securing means bywhich mutually superposed elements are fastened together.

FIGURE 6 is a detail view illustrating the securing means applied to thejoining together of individual indicator units in side-to-side seriesrelationship and of the peripherally located unit to the panel openingedge.

FIGURES 7, 8 and 9 are views illustrating representative arrangements ofmodular dimension indicator units in panel openings.

In the drawings the indicator panel It) has an opening therein of anysuitable shape and size to accommodate one or more indicator unitsarranged in any desired manner within the opening. In FIGURES '1 to 4for convenience in illustration the opening is shown to be of a size andshape'to accommodate only a single indicator unit of rectangularproportions. This indicator comprises a tubular housing device 12,preferably of rectangular cross section, having an inner end wall orbase 14. A com plementally formed tubular indicator device .16 isremovably insertable into the housing, into seated position therein. Theindicator device comprises a base 18 and a lamp cover or shell 29secured to the base by means of one or more screws 22 engageable inthreaded holes 24 formed in the sides of the base 18. The base has aplurality of electric lamp sockets 26 formed therein to receive lampbulbs 49 which are enclosed within the base 13. The outer end wall ofcover 2t forms an indicator screen 28 upon which suitable indicia may beformed or projected optically, depending upon the medium of display.Lamp'base terminals 30 are'adapted to engage cooperable contact elements32,'shown to be of a spring reacting type, mounted in the housing innerend wall or base 14, while common contact is established through anadditional contact element 32' also spring loaded. Binding posts 34; onthe projecting endsof elements 32 (and 32) are provided for securingelectric circuit conductors (not shown) to the contact elements.

.An elastically compressible pad 36 of an elastomeric sealing materialis interposed between the indicator'device base 18 and the housingdevice base 14 and is compressed with the indicator device in seatedposition within the housing. This elastomeric pad, which may comprisefoamed unicellular neoprene or other elastomeric material, has apertures35a therein which pass the projecting contact elements 32. The pad,under compression, forms a moisture seal around the interengaged contactelements 39, 32, with the indicator device seated in the housing.

In order to hold the indicator device 16 seated in the housing, a pairof beryllium copper resilient strips or other resilient metal latch arms40 are carried at opposite sides of the indicator device. These latcharms comprise elongated fiat members which are turned at right angles attheir inner ends, which ends are secured by clamp fasteners 42 to thebase 1%. Shallow grooves 44 in the side walls of the shell 2daccommodate the latch arms and provide spaces for edgewise transverseactuating movement of these arms with the inidcator device inserted inthe housing. Small knobs lilo on the outer ends of the latch armsproject just clear of the front face of the assembled indicator, asshown in FIGURE 1, where they are accessible for manual actuation of thearms. Teeth '46 formed on the respective latch arms intermediate theirends are adapted to engage the locking pins 48 mounted on the inner sidewalls of the housing 12. These teeth have sloping edges facing inwardlyof the housing which engage the locking pins 4-3 as the indicator unitis inserted into the housing and thereby deflect the arms in order topermit the teeth to pass the pins. Transversely oriented outer teethedges, facing outwardly along the latch arms engage the respective pinsto hold the indicator device in seated position. When the latch arms aredeflected manually in order to disengage the teeth from the associatedpins 4&3, the compressed elastic pad 36 expands and ejects the indicatordevice a short distance from its seated position, enabling it to begrasped conveniently for removal from the housing.

The housing itself, 12, is normally not removed from the indicator panelmerely in order to test the circuit at the lamp sockets, nor to replacea burned-out lamp. Instead, in order to replace a lamp, the latchelements are actuated and the indicator device .16 only is removed,whereupon the lamps 49 may be removed "directly from their sockets atthe back side of the base 13.

In order to secure an indicator unit in the panel open ing, one or moremounting brackets 59 are provided which individually comprise plate-likemembers 52 adapted for superpositioning on an adjacent side of thehousing 12. Coincident slots 54 and 56 formed in the housing wall andplate-like element 52 at the inner (i.e., rear) ends thereof have narrowentrance portions and widened base portions interconnected or joined byan abrupt transition preferably of approximately degrees. A nut Ed isinitially placed in the widened base portions of the coincident slots,such nut having a transverse groove 60 formed in one end thereof, whichgroove forms spaced abutments 62 and 64 between which the transitionalportions of the superposed elements are received when the screw 66,which threads into the nut through the entrances of the coincidentslots, is tightened. Such tightetning of the screw draws the nut endwise(away from the back side of the panel) toward the registered ends oftheplatelike element 52 and the housing wall by reaction of the screw headaginst such ends. A lock washer 68 holds the tightened screwagainst-loosening The forward ends of the individual plate-like elements52 extend through the gap or gaps between the housing wall(s) and theadjacent edge(s) 0f the panel opening and carry an outturned flange 74which overlaps the panel edge. Preferably a molding or edging strip 72having a channel portion receiving this flange directly abuts the outerface of the panel and has an inwardly extending flange 74 which isreceived in the gap between the edge of the panel and the adjacent sideof the plate-like element. A mounting post 76 on the side of theplatelike element 52 carries a clamp screw 7 3 having .a bearing element81 on the tip thereof, between which and the flange 70 the panel isclamped when the screw is tightened. Since the bracket 56 is secured tothe side of the housing 12 and since the bracket in turn is secured byclamping action to the edge of the panel adjacent the opening, thehousing itself is firmly secured to the panel. Similar brackets may beprovided on all sides of the housing unit in order to engage all sidesof the panel adjacent the opening therein. The outer side of the channelportion of edging 72 is wider than the inner side thereof so as to coverover the marginal edges of the adjacent indicator units. Use of theedging or head strip 72 simplifies installation by eliminating acritical dimension requirement for the panel opening.

Thus, with indicator units of modular construction wherein the width inone dimension is approximately twice (or approximately some other wholenumber multiple) that in another dimension, a single bracket may beprovided on each of the narrow sides at a central location and one ormore brackets at modular spacing may be provided on each of the broadsides of the unit to match up with the single central bracket mentioned,as depicted in the drawings. As seen best in FIGURE 6, the samescrew-and-nut securing means 66, 53 may be used to secure indicatorunits together as is used to secure indicator units together as is usedto secure an outer or peripherally presented side of a peripherallylocated indicator unit to its associated mounting bracket 52. Of course,the mounting brackets themselves are used only for securing theindicator units to the edges of the panel opening and are not requiredin order to secure indicator units to each other.

FIGURES 7, 8 and 9 illustrate different arrangements of modularlydimensioned indicator units in various types of panel openings. Withmodularly dimensioned indicators, it will be evident that any of manyvaried arrangements are possible. The units may be arranged in rows andcolumns or in staggered of offset relationship and may be orienteddiiferently in different locations suiting requirements of differentapplications. Moreover, the indicator units may be of different shapesand sizes if desired, still utilizing the principles of construction andarrangement herein disclosed.

It will be evident furthermore that the objectives of the invention setforth hereinabove are met by the improved indicator structures andcomponents. The screws 66 and 78 are all accessible directly from therear side of the assembly and a screwdriver may be used to release anyone or more indicators without disturbing the others. in order tocomplete a panel assembly the first step conveniently may be to placethe marginal beading or molding strip 72 in the opening, whereupon it isconvenient to secure the mounting bracket flanges 7a) in the groove inthe molding, in which such flanges may fit snugly and be tentativelyretained. Alternatively, certain of the brackets may first be secured tothe sides of the housing unit or units 12, and thereafter clamped in thepanel opening. Inasmuch as there are often a maze of electric wiresleading to and from the bases of the indicator units in a large panelassembly, the novel securing means operated solely by a screwdriver,which may be applied and withdrawn while held perpendicularly to thepanel, greatly facilitates gaining direct access to the individualfastening elements. Also, the convenience of checking individual circuitpoints or changing lamps entirely from the front side of the panel,simply by removing the indicator devices in in each instance, is afurther advantage.

These and other aspects of the invention will be recognized by thoseskilled in the art on the basis of the foregoing disclosure of thepresently preferred embodiment.

We claim as our invention:

1. An indicator assembly comprising an open-end housing device, acomplementally formed indicator device removably insertable into thehousing device into seated position therein through its open end, saidindicator and housing devices having cooperable electric terminalelements therein, the inserted indicator device having an outer-enddisplay face and having oppositely situated side faces spaced slightlyinwardly from the respectively adjacent housing inner side faces, andinternally contained manually disengageable latch means operable to holdthe indicator device seated in the housing device, including at leastone resiliently acting elongated latch arm having an inner end portionsecured to one of the devices to project therefrom lengthwise throughand along one side space between such devices to be manually accessibleat the open end of the housing device, said latch aim be ing adapted formanual actuation by deflection of the arm parallel to said side face,said latch means further including a latch element carried by the armand a cooperable latch element carried by the other of said devices tobe engaged by the arm-carried latch element accompanying seatingmovement of the indicator device, and adapted to be disengaged manuallyby such arm deflection.

2. The indicator assembly defined in claim 1, wherein the latch meansincludes two oppositely situated latch arms comprising resilientmaterial strips and having inner end portions secured to one of thedevices and relatively thin and wide elongated portions which projectfrom said inner end portions lengthwise through and along theresp-ective side spaces between such devices to be accessible for manualactuation at the open end of the housing device to permit latchactuation by transverse deflection of the arms in their respectiveplanes parallel to said side faces, the arm-carried latch elements beingcarried by one side edge of each arm body portion intermediate its ends.

3. The indicator assembly defined in claim 2, wherein the arms arecarried by the indicator device and each armcarried latch elementcomprises a projecting tooth formation having a gradually sloping edgefacing inwardly of the housing device and an abrupt opposite edge facingoutwardly of the housing device, said tooth formation being engageablewith the associated latch element in the housing device to deflect thetooth formation in passing as the indicator device approaches seatedposition.

-l. The indicator assembly defined in claim 3, further comprisingresilient means carried by one device and compressed by engagement ofthe other device in the final phase of seating the indicator device,whereby the latter is partially ejected from the housing device byrecoil of such resilient means upon releasing the latch elements.

5. The indicator assembly defined in claim 4, wherein the indicatordevice includes an inner end wall and at least one electric lamp socketwith a terminal contact element, comprising the indicator deviceterminal element, contactable at the inner end wall of such device, thehousing device has an inner end wall which carries at least onecooperable contact element, comprising the housing device terminalelements, engageable with the lamp socket contact element by seating ofthe indicator device, one of said contact elements being an elementwhich projects from the associated inner end wall, and thelast-mentioned resilient means comprises a pad of elastomeric materialapertured to pass the projecting contact element and being resilientlycompressed between the inner end walls with the indicator device seated.

6. A plug and socket electrical assembly comprising an open-end socketdevice, a complementally formed plug device removably insertable intothe socket device into eated position therein through its open end, theinserted plug device having an outer-end utilization means and havingoppositely situated side faces spaced slightly inwardly from therespectively adjacent socket inner side faces, and internally containedmanually disengageable latch means operable to hold the plug deviceseated in the socket device, including a pair of resiliently actingelongated latch arms having inner end portions secured to one of thedevices to project therefrom lengthwise through and along the sidespaces between such devices to be accessible for manual actuation at theopen end of the socket device to permit latch actuation by deflection ofthe arms parallel to said side faces, said latch means further includinga latch element carried by each arm and cooperable latch elementscarried by the other of said devices to be engaged by the respectivearm-carried latch elements accompanying seating movement of the plugdevice, and to be disengaged manually by such arm deflection.

7. The plug and socket assembly defined in claim 6, wherein the plugdevice includes an inner end wall and at least one electric connectorwith a terminal contact element contactable at the inner end wall ofsuch device, the

socket device has an inner end wall which carries at least onecooperable contact element engageable with the electric connectorcontact element by seating of the plug device, one of said contactelements being an element which projects from the associated inner endwall, and the last-mentioned resilient means comprises a pad ofelastomeric material apertured to pass the projecting contact elementand being resiliently compressed between the inner end walls with theplug device seated.

8. An electrical circuit terminal panel assembly, comprising a supportpanel having an opening therein, an electrical circuit terminal unitpositioned in said opening with one side'element of said unit separatedby a short gap from one edge of the panel opening, mounting bracketmeans releasably mounting the unit in such position, comprising aplate-like element superposed on said one side element and having oneend positioned substantially in registry with one end of said unit sideelement and extending from said one end through said gap from a firstside of the panel, and immediately beyond said gap having a transverselyprojecting element overlapping the opposite side of the panel at saidedge, clamp means on the platelike element adjacent the first side ofthe panel, cooperable with said transversely projecting element to clampthe panels edge releasably therebetween, and securing means to securethe plate-like element and unit side element together in mutuallysuperposed relationship, such latter means comprising substantiallycoincident slots formed in each, having a relatively narrow entranceportion extending inwardly through a transitional portion into arelatively wide base portion, a first fastener member insertable intothe slot base portions through an open side thereof and havingtransversely spaced abutments projecting endwise from one end thereof,between which abutments the superposed elements at opposite sides of theslot transitional portion are receivable by advancing such fastenermember endwise to a seat in a sense from the base toward the entranceportion of the slots, and a cooperable fastener member securablyengageable with the first fastener member by projection of the secondfastener member through the slot entrance portions from the outer endthereof opposite the slot base portions. i I 9. The combination definedin claim 8, wherein the transversely projecting element comprises aplate-like flange, and an edging strip formation including an innerflange portion lodged in the gap between said panel edge and theadjacent face of the plate-like member, and an outer channel portionjoined transversely to the flange portion and receiving the plate-likeflange therein, said channel having an inner side interposed betweensaid platelike flange and the panel, and an outer side covering theplate-like flange and lapping marginally over the end of the unit.

7 1d. The combination defined in claim 8, wherein registered ends of theelements have extreme end edge portions inwardly from the edge of whichthe respective slots are directed, wherein the slots Widen abruptly, ata transition angle ofat least approximately ninety degrees, from theentrance portion to the base portion thereof, and wherein the secondfastener member has an enlarged outer end portion and is operable whenengaged with the first fastener member to apply outwardly directed forceon the latter member in its seated position, by reaction of saidenlarged outer end portion against said edge.

' 11. The combination defined in claim 10, wherein the second fastenermember comprises a machine type screw having a head which comprises theenlarged outer end portion, and wherein thefirst fastener membercomprises an internally threaded nut having one end grooved transverselyto form the abutments, on opposite sides of the groove. 12. Thecombination defined in claim 11, wherein the depth of the groovesubstantially equals the depth of the slot entrance portion from saidedge to said transition, and wherein the clamp means comprises a postmember mounted on the outer face of the plate-like member, and

a clamp screw threaded transversely through said post member and havingan end element adapted to bear against the first side of the panel.

13. An indicator panel assembly, comprising a support panel having anopening therein, a plurality of indicator units having electric terminalelements therein, said units being positioned generally behind suchpanel with indicator faces disposed generally in the plane of saidopening, at least some of said indicator elements being pe ripherallylocated within said opening, a peripherally located one or" said unitshaving an outer side element separated by a small space from one edge ofthe panel opening, mutually adjacent units having mutually superposedside elements, mounting bracket means releasably mounting a peripherallylocated unit in the panel opening, comprising a plate-like elementsuperposed on said outer side element and having one end positionedsubstantially in registry with one end of said unit outer side elementand extending from said one end through said small space from the backside of the panel, and immediately beyond said space having atransversely projecting element overlapping the front side of the panelat said edge, clamp means on the plate-like element adjacent the backside of the panel, cooperable with said transversely projecting elementto clamp the panels edge releasably therebetween, and similar securingmeans to secure the respective mutually superposed elements together,and thereby secure the units to each other and to the panel, each suchsecuring means comprising substantially coincident slots formed in eachsaid side element, having a relatively narrow entrance portion extendinginwardly through a transitional portion into a relatively' wide baseportion, a first fastener member insertable into the slot base portionsof two adjacent side elements through an open side thereof and havingtransversely spaced abutments projecting endwise from one end thereof,between which abutments the superposed elements atopposite sides of theslot transitional portion are receivable by advancing such fastenermember end- Wise to a seat in a sense from the base toward the entranceportion of the slots, and a second cooperable fastener member securablyengageable with the first fastener member by projection of the secondfastener' member through the slot entrance portions from the outer endthereof opposite the slot base portions.

14. The combination defined in claim 13, wherein registered ends of theside elements have extreme end edge portions inwardly from the edge ofwhich the respective slots are directed, wherein the slots widenabruptly, at a transition angle of at least approximately ninetydegrees, from the entrance portion to the base portion thereof, andwherein the second fastener member' has an enlarged outer end portionand is operable when engaged with the first fastener member to applyoutwardly directed force on the latter member in its seated position, byreaction of said enlarged outer end portion against said edge.

15. The combination defined in claim 14, wherein the 7 second fastenermember comprises a machine type screw having a head which comprises theenlarged outer end portion, and wherein the first fastener membercomprises an internally threaded nut having one end grooved transverselyto form the abutments, on opposite sides of the' groove. 7

16. The combination defined in claim 13, wherein all the peripherallylocated indicator unit outer side elements are similarly releasablymounted on the panel, and wherein the transversely projecting element ofeach securing means therefor comprises a plate-like flange, and anedging strip formation including an inner flange portion lodged in thegap between said panel edge and the adjacent face of the plate likemember, and an outer channel portion joined transversely to the flangeportion and receiving the plate-like flange therein, said channel havingan inner side interposed between said plate-like flange and the panel,and an outer side covering the platelike flange and lapping marginallyover the end of the unit.

17. The combination defined in claim 13, wherein the indicator units areof generally rectangular cross section and of modularly relateddimensions permitting arranging the same in various patterns within agiven opening space, one dimension of each unit being substantially awhole number multiple of the other dimension thereof.

18. The combination defined in claim 17, wherein the Whole numberexceeds one, and wherein the relatively narrow side elements of eachunit have one of the aforesaid slots, centrally located across the widththereof, and the relatively wider side elements each have a number ofsuch slots equal to said whole number, whereby the units may be arrangedselectively with broad sides superposed on either broad or narrow sidesin various modular pattern relationships.

19. An indicator panel assembly, comprising a support panel having anopening therein, a plurality of indicator units having electric terminalelements therein, said units being positioned generally behind suchpanel with indicator faces disposed generally in the plane of saidopening, at least some of said indicator elements being peripherallylocated within said opening, one of said peripherally located unitshaving an outer side element separated by a small space from one edge ofthe panel opening and with side elements of mutually adjacent units eingmutually superposed, mounting bracket means releasably mounting theperipherally located unit in the panel opening, comprising a plate-likeelement superposed on said outer side element and having one endpositioned substantially in registery with one end of said unit outerside element and extending from said one end through said small spacefrom the back side of the panel, and immediately beyond said Spacehaving a transversely projecting element overlapping the front side ofthe panel at said edge, clamp means on the plate-like element adjacentthe back side of the panel, cooperable with said transversely projectingelement to clamp the panels edge releasably therebetween and a pluralityof releasable securing means interconnecting adjacent side elements ofsaid superposed units and interconnecting said plate-like element withsaid outer side element.

20. An indicator panel assembly comprising a support panel having anopening therein, an indicator unit having an electrical terminal elementtherein, and being positioned in said opening with one side element ofsaid unit separated by a small space from one edge of the panel opening,mounting bracket means releasably mounting the unit in such positioncomprising a plate-like element superposed on said one side element andhaving one end extending through said space from a first side of thepanel, and immediately outward from said space, said plate-like elementhaving a transversely projecting portion overlapping the opposite sideof the panel at said edge, clamp means on the plate-like elementadjacent the first side of the panel, cooperable with the panel and saidtransversely projecting portion to clamp the panels edge releasablytherebetween, and securing means releasably securing the plate-likeelement and unit side element together in mutually superposedrelationship.

21. The assembly defined in claim 20, wherein the clamp means comprisesa post member mounted on the outer face of the plate-like member, and aclamp screw threaded transversely through said post member and having anend element adapted to bear against the first side of the panel.

22. The assembly defined in claim 21, wherein the transverselyprojecting portion comprises a plate-like flange, and an edging stripformation including an inner flange portion lodged in the space betweensaid panel edge and the adjacent face of the plate-like member, and anouter channel portion joined transversely to the flange portion andreceiving the plate-like flange therein, said channel having an innerside interposed between said plate-like flange and the panel, and anouter side covering the plate-like flange and lapping marginally overthe end of the unit.

23. An indicator assembly comprising an open-end housing device, anindicator device removably insertable into the housing device intoseated position therein by' relative longitudinal movement therebetween,said devices respectively having transversely extending base surfacesdisposed in proximate substantially parallel relationship with thedevices seated together, cooperating electric terminal meanscorrespondingly positioned in the respective base surfaces forinterengagement by such seating, a pad of elastomeric sealing materialinterposed between and substantially covering said base surfaces inmutual contact therewith and apertured to pass the electric terminalmeans, the thickness of said pad exceeding the spacing between thesurfaces to be resiliently compressed by such seating, thereby to form amoisture seal around the aperture, and latch means carried by therespective devices, operable to hold the indicator device seated withsuch pad compressed.

References Cited by the Examiner UNITED STATES PATENTS THOMAS E.HABECKER, Acting Primary Examiner.

ROBERT H. ROSE, NEIL C. READ, Examiners.

1. AN INDICATOR ASSEMBLY COMPRISING AN OPEN-END HOUSING DEVICE, ACOMPLEMENTALLY FORMED INDICATOR DEVICE REMOVABLY INSERTABLE INTO THEHOUSING DEVICE INTO SEATED POSITION THEREIN THROUGH ITS OPEN END, SAIDINDICATOR AND HOUSING DEVICES HAVING COOPERABLE ELECTRIC TERMINALELEMENTS THERIN, THE INSERTED INDICATOR DEVICE HAVING AN OUTER-ENDDISPLAY FACE AND HAVING OPPOSITELY SITUATED SIDE FACES SPACED SLIGHTLYINWARDLY FROM THE RESPECTIVELY ADJACENT HOUSING INNER SIDE FACES, ANDINTERNALLY CONTAINED MANUALLY DISENGAGEABLE LATCH MEANS OPERABLE TO HOLDTHE INDICATOR DEVICE SEATED IN THE HOUSING DEVICED, INCLUDING AT LEASTONE RESILIENTLY ACTING ELONGATED LATCH ARM HAVING AN INNER END PORTIONSECURED TO ONE OF THE DEVICES TO PROJECT THEREFROM LENGTHWISE THROUGHAND ALONG ONE SIDE SPACE BETWEEN SUCH DEVICES TO BE MANUALLY ACCESSIBLEAT THE OPEN END OF THE HOUSING DEVICE, SAID LATCH ARM BEIN ADAPTED FORMANUAL ACTUATION BY DEFLECTION OF THE ARM PARALLEL TO SAID SIDE FACE,SAID LATCH MEANS FURTHER INCLUDING A LATCH ELEMENT CARRIED BY THE ARMAND A COOPERABLE LATCH ELEMENT CARRIED BY THE OTHER OF SAID DEVICES TOBE ENGAGED BY THE ARM-CARRIED LATCH ELEMENT ACCOMPANYING SEATINGMOVEMENT OF THE INDICATOR DEVICE, AND ADAPTED TO BE DISENGAGED MANUALLYBY SUCH ARM DEFLECTION.